Rave Party is a physical ability, and Neon Kat's signature ability.
Base Power: 5
Element: None (Physical)
Rave Party deals 5 damage from each of the elements. Since there are 10 (Including physical), it pretty much deals 50 damage. Weaknesses and strengths still effect all of the hits.
If you use Monochrome World before you send out Neon Kat (Neon Kat doesn't learn it), combined with a high power stat, Rave Party could deal some pretty high damage alltogether.